P4 - Explain the physiology of two named body systems in relaton to energy
metabolism in the body
In this assignment, I will be explaining the physiology of two named body systems in relaton to energy metabolism
in the body. I will be discussing the digestie system and the cardioiascular system.
Digestve system
The digestie process starts in the mouth. In the mouth, saliiary glands contain
saliiary amylase which mixes with food during mechanical digeston. Saliiary
amylase requires a neutral pH to functon eeectiely. The substrate in the
mouth is starch and the end product is double sugar molecules. The food then
passes through the oesophagus where the saliiary amylase is stll actng, next it
goes into the stomach. Gastric glands within the stomach contain gastric
protease, hydrochloric acid and rennin in babies. The pH of gastric glands has to
be acid in order for the pepsin to be eeectie. ood is churned into chyme and
bacteria found in raw food is killed by the stomach acid. The substrate is
protein and the end products are amino acids and peptdes. ext, the food
traiels down to the small intestne where intestnal glands are found. Inside the
intestnal glands is peptdase and iarious carbohydrates. The substrate is
peptdes and double sugar molecules and the end product is amino acids and
other simple soluble sugars. The liier and pancreas are also iniolied in the digestie process. The liier produces
bile which emulsifes lipids/fats and conierts small intestne contents from acid to alkaline. urthermore, the
pancreas is a iery important digestie gland because the salts within it coniert acid stomach secretons to alkaline,
so that the enzymes can work eeectiely. The pancreas contains lipase, pancreatc amylase, pancreatc protease and
alkaline salts. Afer that, the food goes into the ileum where the main products of digeston are absorbed through
millions of iilli. ext, it enters the large intestne which is the main area for absorpton of water. Lastly, the food
goes into the rectum which are muscular walls that expel semi-solid faeces through the anus.
Cardiovascular system
The main functon of the cardioiascular system is to transport oxygen and nutrients to the liier and cells iia the
bloodstream. The heart pumps blood around the body through arteries, ieins and capillaries. Arteries carry blood
away from the heart to organs under high pressure. Veins carry blood to the heart from the organs under low
pressure. Capillaries connect arteries to ieins. The blood passes through the heart it any one cycle, which is known
as double circulaton. The double circulaton of the heart goes from the lungs to the lef heart pump iia the
pulmonary iein, then from the lef heart pump to the body iia the aorta, next from the body to the right heart pump
iia the iena caia, lastly from the right heart pump back to the lungs iia the pulmonary artery. The circulaton to and
from the lungs is called pulmonary circulaton, and the circulaton around the body is called systematc circulaton.
urthermore, the cardiac cycle refers to the eients that take place in the heart during one heartbeat. The aierage
cardiac cycle is 0.8 seconds. The higher the heart rate the shorter the cardiac cycle. The heart is controlled by the
autonomic nerious system, which has two branches called the sympathetc nerious system (S S) and the
parasympathetc nerious system (P S). The S S is at work during muscular work, stress and fear causing an
increased heart rate. The P S is at work during peace and contentment causing a decreased heart rate. Lastly, blood
contains haemoglobin which is a iery important iron-containing protein. This is because in an eniironment
containing a high concentraton of oxygen, it becomes oxyhaemoglobin when it bonds with oxygen. Oxyhaemoglobin
is what carries oxygen to tssue cells. Also, in an eniironment containing a low concentraton of oxygen, the oxygen
metabolism in the body
In this assignment, I will be explaining the physiology of two named body systems in relaton to energy metabolism
in the body. I will be discussing the digestie system and the cardioiascular system.
Digestve system
The digestie process starts in the mouth. In the mouth, saliiary glands contain
saliiary amylase which mixes with food during mechanical digeston. Saliiary
amylase requires a neutral pH to functon eeectiely. The substrate in the
mouth is starch and the end product is double sugar molecules. The food then
passes through the oesophagus where the saliiary amylase is stll actng, next it
goes into the stomach. Gastric glands within the stomach contain gastric
protease, hydrochloric acid and rennin in babies. The pH of gastric glands has to
be acid in order for the pepsin to be eeectie. ood is churned into chyme and
bacteria found in raw food is killed by the stomach acid. The substrate is
protein and the end products are amino acids and peptdes. ext, the food
traiels down to the small intestne where intestnal glands are found. Inside the
intestnal glands is peptdase and iarious carbohydrates. The substrate is
peptdes and double sugar molecules and the end product is amino acids and
other simple soluble sugars. The liier and pancreas are also iniolied in the digestie process. The liier produces
bile which emulsifes lipids/fats and conierts small intestne contents from acid to alkaline. urthermore, the
pancreas is a iery important digestie gland because the salts within it coniert acid stomach secretons to alkaline,
so that the enzymes can work eeectiely. The pancreas contains lipase, pancreatc amylase, pancreatc protease and
alkaline salts. Afer that, the food goes into the ileum where the main products of digeston are absorbed through
millions of iilli. ext, it enters the large intestne which is the main area for absorpton of water. Lastly, the food
goes into the rectum which are muscular walls that expel semi-solid faeces through the anus.
Cardiovascular system
The main functon of the cardioiascular system is to transport oxygen and nutrients to the liier and cells iia the
bloodstream. The heart pumps blood around the body through arteries, ieins and capillaries. Arteries carry blood
away from the heart to organs under high pressure. Veins carry blood to the heart from the organs under low
pressure. Capillaries connect arteries to ieins. The blood passes through the heart it any one cycle, which is known
as double circulaton. The double circulaton of the heart goes from the lungs to the lef heart pump iia the
pulmonary iein, then from the lef heart pump to the body iia the aorta, next from the body to the right heart pump
iia the iena caia, lastly from the right heart pump back to the lungs iia the pulmonary artery. The circulaton to and
from the lungs is called pulmonary circulaton, and the circulaton around the body is called systematc circulaton.
urthermore, the cardiac cycle refers to the eients that take place in the heart during one heartbeat. The aierage
cardiac cycle is 0.8 seconds. The higher the heart rate the shorter the cardiac cycle. The heart is controlled by the
autonomic nerious system, which has two branches called the sympathetc nerious system (S S) and the
parasympathetc nerious system (P S). The S S is at work during muscular work, stress and fear causing an
increased heart rate. The P S is at work during peace and contentment causing a decreased heart rate. Lastly, blood
contains haemoglobin which is a iery important iron-containing protein. This is because in an eniironment
containing a high concentraton of oxygen, it becomes oxyhaemoglobin when it bonds with oxygen. Oxyhaemoglobin
is what carries oxygen to tssue cells. Also, in an eniironment containing a low concentraton of oxygen, the oxygen
